Rotary oil well drilling apparatus



1932- E. J. LE COMPTE ET AL 1,891,328

ROTARY OIL WELL DRILLING APPARATUS Filed Feb. 25, 1932 5 Sheets-Sheet 1INVENTORS. Z. JZflJZ/YZ/IZE.

I f z a i ATTORNEY. A

1933 E. J, LE COMPTE ET AL 1,891,328

ROTARY OIL WELL DRILLING APPARATUS Filed Feb. 25, 1952 5 Sheets-Sheet '27 INVENTORS.

5 Jiafiq/fzjiia ATTORNEY.

1932' E. JJLE COMPTE ET AL 1,891,323

ROTARY OIL WELL DRILLING APPARATUS Dec. 20, 1932.

E. J. LE COMPTE ET AL 8 ROTARY OIL WELL DRILLING APPARATUS Filed Feb.25, 1932 5 Sheets-Sheet 4 I Dec. 20, 1932- E. J. LE COMPTE ET AL ROTARYOIL WELL DRILLING APPARATUS Filed Feb. 23, 1932 5 Sheets-Sheet 5ATTORNEY.

Patented Dec. 20, 1932 UNITED STATES PATENT ()FFICE EDWARD 3'. LE COMPTEAND CARTER A. HARRISSON, OF ST; LOU IS, MISSOURI, AS- SIGNORS TONATIONAL OIL DRILL CORPORATION, OF ST. LOUIS, MISSOURI, A :COR-

PORA'IION F DELAXVARE ROTARY OIL WELL DRILLING APPARATUS Applicationfiled. February 23, Serial No. 594,540.

Our invention relates to deep oil well drilling apparatus.

In deep oil well drilling, it is a well known fact to drillers, that acertain predetermined pressure should be applied to drill bits, and nomore, which pressure varies accordng to earth formations, to insure thehighest efficiency in the cutting of certain earth formations,particularly hard earth formations, such for instance as granite, or thelike, and that greater pressure on the bit than that recommended bymanufacturers of bits for the various formations, quickly dulls thedrill cones and often crushes the same, incurring unnecessaryinconvenience and expense to the driller, besides aggravating thetendency of the bit to cut at an angle-to the straight hole desired.

Our invention has for an object, the provision of telescopic meansconnected into the rill stem line at a predetermined section in thelength thereof, which telescopic means is employed in lieu of a certaindrill stem section, and itis provided with means to set up a backpressure of mud laden fluid when partly collapsed, said telescopic meanspermitting a predetermined pressure, gauged by the weight of the drillstem section below the telescopic means, being uninterruptedly appliedto the drill cones, to avoid unnec-es sary dulling of the bit, avoid.possible crushing of the bit when drilling through hard earth formation,and, in general, thereby facilitate the drilling of an approximatelystraight hole to any depth.

A further object of the invention resides in the provision of meansco-acting with the telescopic drill stem section and actuated by theback pressure of mud laden fluid built up above the telescopic drillstem "section to the mud pump, to indicate to the driller, by thelighting of a signal'lamp, that the progress of the bit into the earthformation is relatively slower than the feeding of drill stem disposedabove the telescopic drill stem section.

A still further object of the invention resides in the provision ofbrake actuating mechanism co-acting with the telescopic drill stemsection. and actuated by the back pressure of mud laden fluid betweenthe drill stem section and the mud pump for austop further lowering ofdrillstem above the telescopic drill stem s'ect1on altogether until suchtime as additional upper drill stem should be lowered into the holewithout adding to the predetermined weight of the drill stem sectionsbelow the telescopic drill stem section. V

A still further obj-ectof the inventionres sides in the provision ofdeep oil well drilling apparatus which possessesv advantages in pointsof simplicity and efficiency, and, at the same time proves itselfcomparatively inexpensive in cost of manufacture.

WVith the above and other objects in view, the invention consists in thenovel features of construction, arrangement and combination of partshereinafter more fully described and finally pointed out in the claimshereto appended.

Referring to the accompanying drawings forming a part of thisspecification, wherein like characters of reference denote similar partsthroughout the several views:

Fig. 1 is a view of a rotary oil well drilling apparatus including theembodiment of our invention.

Fig. 2 is a slightly enlarged view of the drilling apparatus includingthe embodiment of our invention, the upper end of the derrick beingbroken away, and certainparts ofthe apparatus not being shown, such forinstance, as the mud pump and the steam boiler.

Fig. 3 is a sectional view of a telescopic drill stem section embodyingthe features of our invention and with part of one of the membersthereof broken away.

Fig. 4: is a view partly in sideelevation and partly in sectionalelevation, of a string of connected drill stems and adrilling bit on thelower end thereof, including our I telescopic drill stem section, andshown as inoperation in an oil well bore with the telescopic drill stemsection in its furtherestextended position.

Fi 5 is a view similar to Fig. 4, showing.

telescopic 7 the telescopic drill stem section as partly collapsed,which would set up a back pressure of mud laden fluid sufficient todisplay a yellow warning light to the driller, indicating to him thatthe drill bit is not entering the earth formation as fast as the drillstem is being lowered from the derrick.

Fig. 6 is a view similar to Figs. 4 and 5, showing the telescopic drillstem section as further collapsed causing a higher back pressure of mudladen fluid to be built up above the telescopic drill stem section, andcausing a red danger light to be displayed to the driller, indicating tohim, that the drill bit is still not entering the earth formation asfast as the drill stem is being lowered into the well bore above thetelescopic drill stem section, and that there is danger of addedpressure being applied to the drilling bit unless lowering of drill steminto the hole above the telescopic section is stopped.

Fig. 7 is a view similar to Figs. 4, 5 and 6, clearly showing thetelescopic drill stem section as being fully collapsed, but that theflow of mud laden fluid has not stopped its circula tion therethrough.

Fig. 8 is a detail in sectional view of the upper end of the telescopicdrill stem section,

clearly showing the nozzle arrangement and thepressure controlling stemthereof.

Fig. 9 is a detail in perspective of one portion of the outer member ofthe telescopic drill stem section.

Fig. 10 is a detail in perspective of the upper end of the inner memberof the telescopic drill stem section.

Fig. 11 is an enlarged sectional view of the telescopic drill stemsection taken on line 1111 of Fig. 8.

Fig. 12 is an enlarged sectional view of the telescopic drill stemsection, taken on line 12-12 of Fig. 5.

Fig. 13 is an enlarged sectional view of the telescopic drill stemsection, taken on line 13-13 of Fig. 6.

Fig. 14 is an enlarged sectional view of the telescopic drill stemsection, taken on line ld-ll of Fig. 7.

Fig. 15 is a detail, in side elevation, of the brake actuatingmechanism.

Fig. 16 is a front elevation of the electric signal device.

Fig. 17 is a view partly in sectional elevation and partly in sideelevation of the electric signal device.

Fig. 18 is a detail of the manually actuated switch member of theelectric signal device.

Fig. 19 is a view taken on line 1919 of Fig. 17. 1

.Fig. 20 is Fig. '19. V I

s intimated above, our invention resides in the provision of means,first, to permit the drilling bit to progress in depth through hardearth formation, a predetermined disa view taken on line 2020 of tance,with a predetermined drill stem pressure on the drilling bit, or cones;second, in the provision of means to display a safety signal, preferablya green light, during the period of time that drilling is normal, andthat upper drill stem being lowered by a cable, is approximately in thesame speed relation as to the progress made by the drilling cones;third, to display a warning signal when the telescopic drill stemsection has collapsed or shortened the lowering of drill to apredetermined length; fourth, to display a danger signal when thetelescopic drill stem section has collapsed to a predetermined shorterlength; fifth, to li htly actuate a brake mechanism when the warningsignal is displayed, and sixth, to fully set the brake actuatingmechanism when the danger signal is displayed to stop further loweringof upper drill stem until the bit has progressed sutficiently tolengthen out the telescopic drill stem section.

It should be borne in mind, that our primary aim is, at all times, tomaintain a pre determinedpressure, by weight of a lower section of drillstem on the bit, and no more, to display a safety signal during theperiod of normal drilling, to display a warning signal when thetelescopic drill stem section has collapsed to a predetermined length,to display a danger signal when the drill stem has been collapsed to apredetermined shorter length, and to actuate a brake mechanism, first,but lightly when the warning signal is displayed and to fully set thebrake actuat ing mechanism with the display of the danger signal.

First, we shall describe part of the usual drilling apparatus, withwhich our invention is used for efficient rotary deep oil well drill- Aing.

In the drawings, preferably Fig. l, we have illustrated the greater partof a deep well rotary drilling apparatus which consists,

as shown, of the usual derrick A, including over which the cable ridesand which supports the weight of'an upper section of connected drillstems designated H. The connections between the upper drill stem sectionH and the traveling block G being a hook I, a swivel member J, and abail connection K. It also includes a mud laden fluid hose L havingconnection at one end with the swivel member J and its opposite end witha mud laden fluid conducting pipe M, which has connection at one endwith the usual mud pump N. A steam boiler designated. 0 also forms apart of the usual well drilling apparatus and from which extends thesteam conducting pipe P. It may be added that the cable drum is providedalso with the usual brake lift) character T designates the mud fluidpressure gauge which gives the readingof pressure that the mud ladenfluid is being pumped into mud pipe M and through the drill stem line,as will be more fullyset out hereinafter.

In carrying out the aim of our present invention, we employ, inconnection with the drilling apparatus described, what we term a drillstem line length compensator designated generally in Fig. 1, as U, whichis suitably connected at its upper end to the lower end of the upperdrill stem section H; a lower drill stem section of predetermined lengthand designated generally in Fig. 1, as V; an electric signal devicedesignated generally in Fig. 1, as TV and a brake setting and releasingmechanism designated generally in Fig. 2, as 'X TVe shall now describewhat we have hereinbefore referred to as the drill stem lengthcompensator U, or the telescopic drill stem section.

The length compensator, or telescopic drill stem section U is employedand connected with and between the upper drill stem section H and thelower drill stem section V, and the lower drill stem section V carriesthe usual drilling bit Y at the lower end thereof.

The telescopic drill stem section U comarises as shown in detail in Fi 3a stron 7 D 7 O metallic outer and upper tubular member 1 of suitablelength, and which is approximately the length of the usual drill stemsection. A suitable semi-circular metallic facing member 2, acting as akey or rib, is either the lower end thereof, as clearly shown in' Fig.3. The tubular member 1 is provided near its lower end with a fixedinternal ring 3 acting as a stop.

The lower end of the tubular member 1 is internally screw threaded, asat 4, and receivable in this lower screw threaded end of the tubularmember 1, is an externally screw threaded gland 5, between the inner endof which, and the lower end of the fixed stop ring 3, a suitable packing6 is disposed.

Telescopically connected with the outer tubular member 1 of the lengthcompensator, is a suitable inner and lower tubular member 7. Telescopicmember 7 is provided at its upper end with an outer semi-circularmetallic facing designated 8, the side edges of which have longitudinalsliding engagement with the longitudinal side edges of the internalfacing member 2 of the outer tubular member 7 which internal structureof the two tubular telescopic members prevents rotary movement of eithermember relative to the other, but permits longitudinal telescopicmovement of the two members relative to each other, the purpose of whichis to permit the length compensator to be shortened and lengthened,

as will be more clearly understood hereinafter. The upper edge of theinternal ring 3 acts as a stop for the lower edge of the seg- -mentalouter facing 8 of the tubular member 7 to engage for limiting extensionmovement of the two telescopic members. The inner tubular member 7passes downwardly through the aforesaid packing and the gland, H asclearly shown in Fig. 3. The packing 6' prevents possible leakage of mudladen fluid carried in the drill stem line from passing between thetubular telescopic members and by passing into the return fluid andouttlngs surrounding the drill stem line.

The upper end of the outer telescopic mem her 1 is internally screwthreaded, as at 9, for receiving the externally screw threaded portion10 of a nozzle head 11. The nozzle head 11 depends into the outertelescopic member 1 a suitable distance, and extending downwardly fromthe nozzle head 11, is a mud laden fluid pressure controlling stem 12.The stem 12 is straight and of uniform diameter for a predetermineddistance of its length, and

from there on to the lower end thereof, it is gradually tapered, as at13.

The nozzle head 11 is provided with the passage 14 which communicates atits lower end with a plurality of laterally directed nozzle, ordischarge openings 15 formed in the upper end of the pressurecontrolling stem 12. The nozzle openin gs 15 have inclined wall sections16 for directing mud laden fluid downwardly and outwardly therefrom intothe outer tubular telescopic member 1. A plurality of channeled mudladen fluid con ducting grooves 17 are formed on the face of the stem12. These grooves run longitudinally of the pressure controlling stem12, and 5 the upper ends thereof communicate with the nozzle openings15. The lower end of the fluid conducting grooves 17 terminate in theface of the tapered section 1370f the stem by fading out. The grooves 17are preferably,*'- although not necessarily, parallel with one another.

When the telescopic drill, stem section V is in its furthermost extendedposition, the

point of the mud laden fluid pressure controlling stem is a considerabledistance from entrance into the upper end of the inner telescopc drillstem member/Z, which distance is determined by the length of the device.

\Vhatever this distance may be, the dis" tance the drilling bit Y canpenetrate, or cut into the earth formation before any back pressure ofthe mud laden fluid .is built up, greater than the normal working headpressure. Just as soon as the outer telescopicmember 1 has telescopedthe inn-ertelescopic member 7 sufficiently to cause the tapered end 13of the stem 12 to enter the upper end of the inner telescopic member 7,back pressure of the mud laden fluid will start to build up and as thestem continues to enter member 7, the fluid gradually builds up greaterback pressure from the telescopic drill stem section U to the mud pumpN, but at no time is the circulation of the mud laden fluid completelystopped, as the stem groove 17 will always permit a quantity of mudladen fluid to continue to flow through the length compensating deviceU. Also, when fully collapsed, there a small clearance space between thestraight stem section 12 and the inner wall of the inner telescopicmember 7. It is important that the flow of mud laden fluid should not bestopped altogether for the reason such a great back pressure may bedeveloped as to break the hose L, or injure the mud pump.

\Ve shall now describe the hydraulically operated signal, which isautomatically operated by the telescopic movements of the lengthcompensator U connected in the drill stem line.

The electric signal comprises, in part, a Bourbon gauge housed in acasing 18, and the gauge consists of a casing 19 provided with agraduated pressure indicating dial 20, a closed curved elastic tube 21,the free, or closed end of which actuates a registering pointer 22 fixedto a shaft 23. The pointer 22 is actuated through the medium of a link24 su tably connected to the free end of the elastic tube 21 andpivotally connected at its opposite end to the outer end of an arm 25pivoted, as at 26. Arm 25 is provided at its inner end with a pluraltiyof gear teeth 27 engaging a pinion gear 28 carried by the pointer shaft23. The open end of the elastic tube 21 has connection with an orificedcoupling 29 which coupling is also connected with a suitable pipe 30leading to the lower end of a fluid container 31. The fluid container 31is connected through the medium of a suitable pipe connection 32 havinga restricted orifice 33 with the mud laden fluid conducting pipe M,which connects the mud pump N with the swivel joint J at the upper endof the upper section of drill stem. The signal casing 18 is fixed to asuitable post, or support 34 separated from the derrick A so as toarrest as much as possible vibrations imparted to the-electric signaldevice.

Positioned in advance of the Bourbon gauge case 19 is a suitablemanually actuated fiber switch member 35, which i s rotatably supportedon a shaft 36 in axial alignment with and in advance of the pointershaft 23. The fiber switch member 35 is provided'with a suitableoperating handle 38 which passes through an opening 39 in case 18 andwhich is provided with a pointer 40 to register with a selected readingof a graduated pressure dial 41 fixed to the electric signal case 18,and which pressurereading corresponds to the pressure readings of thedial of the Bourbon gauge and the pressure readings of the switch dial.

The opposite face of the switch member.

35 is provided near its edge, in arcuate algned position, with threeelectric contact terminals designated42, 43 and 44, which to the drillerrepresenta safety light zone, awarning light zone and danger light zone,respectively. The warning contact terminal 43 is relatively shorter inlength than the safety contact terminal 42 and the danger contactterminal 44, and the warning contact terminal is interposed between theother two contact terminals, but insulated therefrom, as at 45.

Leading from each of the switch contact terminals 42, 43 and 44 arethree conductors 46, 47 and 48, respectively. These conductors lead,respectively, to three electric lamps designated 49, 50 and 51, whichare supported by a partition 52, in suitable spaced relation, at theforward end of the signal casing 18 and behind aplurality of lensesdesignated 53, 54 and 55, respectively, and each conductor is connectedwith a conductor 56 leading to one side of a source of electricalsupply.

The pointer 22 is provided to one side thereof and movable with thepointer and its shaft, with a suitable resilient yielding brush 57,which is connected with an electrical conductor 58 leading totheopposite side of the source of electrical supply, which may be abattery 59, or any other suitable source of supply. i

hen the pointer brush engages the switch plate contact terminal 42, thegreen light will be displayed, when the pointer brush 57 en gages theswitch plate contact terminal 43, the yellow light will be displayed,and when the pointer brush engages the switch plate 1 contact terminal44, the red light will be dis played.

Thus, for instance, the lamp 49 is connected into what is knownherein'as the safety circuit controlling a green light. The lamp 50 isconnected into what is known herein as a warning circuit controlling theyellow light and the lamp 51 is connected into what is known herein asthe danger circuit controlling the red light.

We shall now describe what we term the hydraulic brake actuatingmechanism, which is also operated by the telescopic movements of thelength compensator U connected into the drill stem line.

As shown in detail in Fig. 15, the cable drum brake actuating mechanismembodies a brake setting lever 60, which can be manually actuatedthrough the handle 61, when so desired, instead of being automaticallyactuits ated hydraulically, as will be apparent hereinafter.

The brake lever is fixed at its lower end to a rock shaft having a crank62, which rock shaft is journaled in suitable bearings 63 fixed to thefloor of the derrick A. The crank 60 is connected with the free end of abrake band 64 riding over the cable drum D by per drill stem sectioninto the well'vhole bored by the drilling bit. 8

The means for automatically actuating the brake lever comprises a steamcylinder 67 ivotally supported as at 68 to the floor of the derrick A.The steam chamber 69 of the cylinder is provided with piston 70connected to the lower end of a piston rod 71, which leads upwardlythrough the upper end of the cylinder. The upper end of the piston ispivotally connected by a removable pin 7 2 to an arm 73, which arm ispivotally connected, as at 74, to a coupling 7 5, suitably clamped tothe brake lever 60. V

A suitable inclined leg 76 is fixed to, and

direct-ed upwardly at an angle toward the longitudinal axis of the lever60, and is provided with a channeled foot 77 adapted for sliding contactwith the brake lever 60 above 1 the clamp coupling 75. The lever arm 73is movablein an arcuate path by means of the piston rod 71. steam chest78 of the steam cylinder 67, is a series of swivelly connected steaminlet pipes designated generally as 79, which are connected at theeutlet ends thereof to a valve case 80 and with which case is alsoconnected a steam pipe 81, which is a branch connection from the steampipe P leading from the steam boiler O. A. mud laden fluid carrying pipe82, whichiis a branch from the mud laden fluid conducting pipe M is alsoconnected with the valve case 83. The valve case 88 is provided with asuitable slidable valve 84 which when the mud pump pressure is normalfor safe drilling, the mud pressure against one end of the slidablevalve 84 al lows the valve to open only suiiiciently against a suitablespring 85 to permit steam to pass through valve groove 86 to set thebrake with such tension as to allow the cable drum to revolve at a speedto lower upperincreases from normal, due to the collapsible telescopicaction of the drill stem length Connected at one end with compensator U,the valve will be opened sulficiently to'admit more steam into the steamcylinder for quickly raising the piston therein to move the brake lever60 to quickly set the brake against the cable drum to prevent furtherlowering of'the upper drill stem section into the well hole. i

The sliding valve action is automatic as to both the mud laden fluidpressure and the steam, thus the setting of the brake is automaticrelative to the amount of back pressure developed in the upper drillstem section by the telescopic action of the length compensator U.

When the compensator device U is fully extended,or even collapsed up tothe point that the free end of the pressure control 12 is just about toenter the upper end of the inner telescopic member 7, the normal workingpressure of the mud laden fluid, which we will say for the purpose ofillustration only is five hundred pounds, the green light of the signalwill be displayed and the steam and mud fluid valve will be in suchposition as to admit such amount of steam into the cylinder 67 as to setthe brake to permit the cable drum to revolve at such speed as to lowerupper drill stem into the hole at a predetermined speed.

/Vhen the length compensator U has collapsed to a point where thetapered section 13 ofstem 12 has entered the upper end of the inner orlower telescopic member 7 sufliciently to set up a back pressure to thepump, of say, for illustration only, five hundred fifty pounds byrestricting the flow of mud laden fluid through the compensator U, theyellow light will be displayed and the green lightwill go out, andsimultaneously therewith, the slidable valve 84 will be slightly movedby the increased pressure of the mud laden fiuid,allowing more steam toenter the cylinder 67 having the bleeder valve 87, to further set thebrake and slow up feeding of upper drill stem into the hole I Now, ifthe drill bit continues to cut slowly, by having encountered very hardearth formation, and the slow lowering of upper drill stemis faster thanthe progress of the bitY, the outer telescopic member 1 will con tinueto move toward thelower telescopic member 7 ,causing the control stem 12to further enter the upper end of the lower telefl scopicmember, andwhen at such position, say for instance, as to restrict the passage ofthe lower telescopic member 7, as'to cause, say for purpose ofillustration only, a back pressure of mud laden fluid to be built up tosix hundred pounds back to the pump, point er of the electric signaldevice will have opened the danger circuit of the device to display ared light and the yellow light will go I out, and,simultaneouslytherewith, the slidfing valve 84 will have been fullyopened and the pressure entering the cylinder 67 andacting against thepiston 70 will cause the brake band to be fully set againstthe cabledrum, preventing the further lowering of the upper drill stem section Huntil at such time as the bit will have progressed in its cutting operation sufficiently to lengthen the compensator light the yellow light,which simultaneously causes the: sliding valve to slightly close,admitting less steam to cylinder and causing a slight let up on thebraking action.

' Now, if the cutting of the bit is faster than the lowering of theupper drill stem section H,- the back pressure will gradually recede,until the pressure in the compensator U and upper drill stem section isnormal working pressure, due to the stem having extracted itself fromthe lower telescopic member 7 caused by lengthening of the compensator Uthrough the telescopic action thereof. When normal pressure is againrestored, the yellow light will go out and the. safety circuit isopened, lighting the green light, and simultaneously therewith thesliding valve 84 will be furtherclosed to allow normal lowering of theupper drill stem section H.

Thus, it will be seen that at no time can the upper drill stem sectioncome into contact and rest upon the lower drill stem section to add allits weight to the drilling bit, as the brake is set before thetelescopic device has been fully collapsed. If through an accident, theupper drill stem should add its weight to the bit, the circulation ofmud fluid would not be stopped as the complete telescoping of thecompensator U will'not shut off the flow, but would merely light the redlight and stop the lowering of further upper drill 40 stem. The bit isintended to be entirely safe from the weight of the upper drill stem atall times so that a predetermined weight can always be applied to thebit as recommended by the manufacturers of the bit for the various earthformations.

The outer member 1 of the telescopic device U is provided with aplurality of suitably spaced peripheral wear rings designated 85.

From the foregoing description, it is evident, that we provide a welldrilling apparatus wherein telescopic means is employed that will permitof a predetermined pressure being applied to the drilling bit, or cones.throughout the drilling operation, wherein an electric signal device ishydraulically controlled to indicate by lightsto the driller theprogress of the bit into the earth formation, and, also wherein anautomatic brake actuating mechanism is hydraulically controlled forlowering drill stem above the telescopic means into the hole in timedrelation to the cutting progress made by the drilling bit. 7

The many advantages of the herein described invention will readilysuggest themselves to those skilled in the art to which it appertains.

From the foregoing description, it is evident that a simple device forthis purpose has been disclosed, but it is to be understood that we'donot desire to restrict, or limit ourselves to the very details of theconstruction shown and described, which is merely illustrative, it beingobvious that changes, not involving the exercise of invention, may bemade without conflicting or departing from the spirit of the inventionwithin the scope of the append ed claims.

What we claim is:

1. A drill stem section comprising apair of tubular members arranged intelescopic relation; means to restrict rotary movement of said tubularmembers with respect to each other; and a head having an elongated stemportion extended therefrom which is tapered for a substantial portion ofits length; said head and stem portion having a fluid passageway formedwithin the interior thereof; said head and stem portion being associatedwith one of said tubular members and being movable therewith and withrespect to the other tubular member so as to cause said stem portion toenter said other tubular member when sufiicient telescopic movement ofsaid tubular members takes place and progressively less-en the area of aportion of the bore of said other tubular member as. the tapered steinportion moves into said bore of said other tubular member.

2. A drill stem section comprising a pair of tubular members arranged intelescopic relation; means to restrict rotary movement of said tubularmembers with respect to each other;and a head having an elongated stemportion extended therefrom which is tapered for a substantial portion ofits length; said head and stem portion having a fluid passageway formedwithin the interior thereof which is provided with an open end at thesurface of said stem portion; said head and stem portion beingassociatedwith one of said tubular members and being movable therewith and withrespect to ti 0 other tubular member so as to cause said stem portion toenter said other tubular member when sufficient telescopic movement ofsaid tubular members takes place and progressively lessen the area of aportion of the bore of said other tubular member as the tapered stemportion moves into said bore of said other tubular member.

3. A drill stem section comprising a pair an elongated groove fozfmed inthe surface of said ste a portion and communicating with the open end ofsaid fluid passageway; said head and stem portion being associated withone of said tubular members and being movable therewith and with respectto an end of the other tubular member so as to cause said stem portionto enter said end of said other tubular member when suflicienttelescopic movement of said tubular members takes place and therebylessen the area of the end portion of the bore 0; said other tubularmember. 7

l. A drill stem section comprising a pair of tubular members arranged intelescopic relation; means to restrict rotary movement of said tubularmembers with respect to each other; and a head having a stem portionextended therefrom; said head and stem portion having a'fluid passagewayformed within the interior thereof which is provided with an open endatthe urface of said stem portion; an elongated groove formedlongitudinally in the surface of said stem portion and communicatingwith the open end of said fluid passageway; said head and stem portionbeing associated with one of saidtubular members and being movabletherewith and wi h respect to an end of the other tubular member so asto cause s id stem portion to enter said end of said other tubularmember when suflicient telescopic movement of said tubular members takesplace and thereby lessen the area of the end portion of the bore of saidother tubular member.

5. A drill stem section comprising a pair of tubular members arranged intelescoping relation; means to restrict rotary movement of said tubularmembers with respect to each other; a head having an elongated stemportion exte ded therefrom which is tapered for a substa tial portionofi s length; a fluid passageway formed in said head andstem portion andextended.longitudinally thereof; and liuid passageways communicatingwith said longitudinal fluid passa eway and having open ends at thesurface or said stem portion; said head and stem portion beingassociated with one of said tubular members and being movable herewithand with respect to 7 other tubular member so as to cause said stemportion to enter said other tubular member when sufiicicnt telescopicmovement of said tubular members takes place and progressively lessenthe area of a of said tubular members with respect to each other; a headhaving an elongated stem por tron extended therefrom which is taperedfor r a substantial portion of its length; a fluid tubular members andbeing movable therewith and with respect to the other tubular member. soas to cause said stem portion to enter said other tubular member whensufficient telescopic movement of sa1d tubular members takes place andprogressively lessen the area of a portion of the bore of said othertubular member as the tapered stem portion moves into said bore of saidother tubular member. 7. A drill stem section comprising a pair oftubular members arranged in telescopic relation; means to restrictrotary movement of said tubular members with respect to each other; ahead having a stem portion extended therefrom; a fluid passageway formedlllSEtlCl head and stem portion and extended longi-' tudinally thereof;and fluid passageways communicating with said longitudinal fluidspassageway and having open ends at opposed points of the surface ofisaidstem'portion;

elongated grooves formed longitudinally in the surface of said stemportionrand communicating with the fluid passageways havlng open ends atsa1d surface of said, stem portion; said head and stem portion being associated with one of said tubular members and being movable therewithand with respect to an end of the other'tubular member so asto causesaid stem portion to enter said end of said other tubular member whensufficient telescopic movement of said tubular members takes place andthereby lessen the area ofthe' end portion of the bore of said othertubular member. I

' 8. A drill stem section comprising a pair 3 of tubular membersarranged in telescopic I'QlfiillOlI; means to restrict rotary movementof sa1d tubular members with respect to each other; and a head having astem portion and I provided with a fluid passageway formed within theinterior thereof; said h ad and other tubular member; said stem portionbeing adapted to enter said end of said other tubular member whensufiicient telescopic movement of said tubular members takes place andthereby lessen the area of the end portion of the bore of said othertubular member.

9. 'A drill stem section comprising a pair of tubular members arrangedin telescopic relatlon; means to restrlct rotary movement of sa1dtubular members wlth respect to each other; a headihaving a stem portionand proe vided with a fluid passageway formed within the interiorthereof; said head and stem portion being associated w1th one of saidtubular members within the bore thereof and being movable therewith andwith respect to an end of the other tubular member; said stem portionbeing adapted to enter said end of said other tubular member whensuflicient telescopic movement of said tubular members 10' takes placeand thereby lessen the area of'the end portion of the bore of said othertubular member, and means for limiting telescopic movement of saidtubular members so as to prevent said head from completely; closing theend of the bore of said other tubular member. 7.

10. A string of connected oil well drill stems divided into an uppersection and a lower bit supporting section; said drill stems beingprovided with fluid passageways formed therethrough; a telescopic drillstem section connected into the string of drill stems and interposedbetween the upper section and the lower bit supporting section;

said telescopic drill stem section comprising a pair of tubular membersarranged in telescopic relation; a head having a stem portion associatedwith one of said tubular members within the borethereof and movabletherewith and with respect to an end of the other of said tubularmembers in a manner to affect the pressure of fluid passing through thestring of drill stems; and a fluid passageway formed within the interiorof said head and stem portion through which fluid passing through thestring of drill stems moves.

11. A string of connected oil well drill stems divided into an uppersection and a lower bit supporting section; said drill stems beingprovided with fluid passageways formed therethrough; a telescopic drillstem section connected into the string of drlll stems and interposedbetween the upper section and the lower bit supportingsection;

said telescopic drill stem section comprising a pair of tubular membersarranged in telescopic relation; a head having a stem portion associatedwith one of said tubular members within the bore thereof and movabletherewith and with respect to an end of the other of said tubularmembers in a manner to affect the pressure of flu1d passmg through thestring of drill stems; and a fluid passageway formed within the interiorof said head and stems and interposed between the upper section and thelower bit supporting section; said telescopic drill stem sectioncomprising a pair of tubular members arranged in telescopic relation; ahead having a stem portion associated with one of said tubular memberswithin the bore thereof and movable therewith and with respect to an endof the other of said tubular members in a manner to affect the pressureof fluid passing through the string of drill stems; a fluid passagewayformed within the interior of'said head and stem portion through whichfluid passing through the string of drill stems moves, said fluidpassageway in said head and stem portion being open at the surface ofsaid stem portion, and means for pumping fluid through the fluidpassageways formed through said drill stems and said head and stemportion.

13. A string of connected oil well drill stems divided into an uppersection and a lower bit supporting section; said drill stems beingprovided with fluid passageways formed therethrough; atelescopic drillstem section connected into the string of drill stems and interposed.between the upper section and the lower bit supporting section; saidtelescopic drill stem section comprising a pair of tubular membersarranged in telescopic relation; a head having a stem portion associatedwith one of said tubular members within the bore thereof and movabletherewith and with respect to an end of the other of said tubularmembers in a manner to affect the pressure of fluid-passing through thestring of drill stems; a fluid passageway formed within the interior ofsaid head and stem portion through which fluid passing through thestring of drill stems moves; said fluid passageway in said head and stemportion being open at the surface of said stem portion, means forpumping fluid through V the fluid passageways formed through said drillstems and said head and stem portion, and means for limiting telescopicmovement of said tubular members so as to prevent said head fromcompletely closing the end of the bore of said other tubular member.

14. A drill stem section comprising a pair ing through a portion of thecontinuous fluid passageway.

15. In combination, a string of rotary oil well drill stems divided intotwo sections telescopically connected together in a manner to permitrelative longitudinal movement between said two sections, said twosections being provided with related openings formed therethrough whichproduce a continuous fluid passageway through which fluid may be pumped,and an element of unsymmetrical cross-sectional shape associated withone of said two sections between which element and the opening formedthrough the other of said '15 two sections relative movement takes placeon relative movement of said two sections, such relative movement ofsaid element and said opening serving to progressively decrease andincrease the effective area of a portion of said opening, whereby thepressure of fluid passing through a portion of the continuous fluidpassageway is varied.

In testimony whereof, we have hereunto aflixed our signatures. EDWARD J.LE COMPTE. CARTER A. HARRISSON.

